I was joining Drybone Behest where I joined a party forming I saw a player on his 50 BLM that wasn't joining the party. When the behest started he mounted up proceeded to kill all the mobs except boss mobs that where level 24 since he was in the behest and thus was unkillable on classes we where trying to level, So I sent a GM ticket about griefing and soon got the reply that this wasn't something the GM's could do anything about.

So is it true can you just waltz around ruining people's event and such and GM's will not do anything about it?